Identification of Pneumocystis carinii f. sp. hominis gene sequences in filtered air in hospital environments

To evaluate the risk of a nosocomial spread of Pneumocystis carinii f. sp. hominis (P. carinii hominis), air filter samples from rooms of P. carinii pneumonia (PCP) patients, adjacent corridors, and other hospital environments have been investigated for the presence of P. carinii hominis. Amplified DNA from air filters and sputum or bronchoalveolar lavage samples from the PCP patients have been genotyped with the P. carinii hominis genes of the mitochondrial large-subunit (mtLSU) rRNA and the internal transcribed spacers (ITS1 and ITS2) of the rRNA. Genotypes of the two loci were identified by direct sequencing, and for site 85 of the mtLSU locus, three allele-specific PCR assays were used. P. carinii hominis DNA was identified in the air of five of seven PCP patient rooms and in the air of two of four air filtrations from the ward corridors. The P. carinii hominis genotypes were the same in four of the five room air samples as those in the corresponding patients, suggesting a risk of person-to-person transmission of P. carinii hominis from PCP patients. Three of 16 air samples collected in infectious disease wards without the presence of PCP patients and one sample from a cardiology unit in a separate hospital building were also positive, which further strengthens the possibility of acquisition of P. carinii hominis from the environment.     

Mutation analyses of KRAS exon 1 comparing three different techniques: temporal temperature gradient electrophoresis, constant denaturant capillary electrophoresis and allele specific polymerase chain reaction

Pefloxacin plus metronidazole versus netilmicin plus metronidazole in the prevention of nosocomial infections during contaminated surgery. Surgical prophylaxis is widely used in contaminated surgery, especially colorectal surgery. In this clinical trial the efficacy of pefloxacin 800 mg i.v. slow infusion associated to metronidazole 500 mg i.v. 1-2 hours before surgery and then metronidazole alone after 6 and 12 hours versus netilmicin 200 mg i.m. associated to metronidazole 500 mg i.v. 1-2 hours before surgery and then both after 6 and 12 hours were evaluated in 97 patients suffering by colorectal surgery. Efficacy of prophylaxis in patients was evaluated in terms of appearance of post-surgical infections (abdominal, urinary, respiratory and wound infections). In pefloxacin + metronidazole group (53 patients), two cases of wound infections (3.8%) and three cases of respiratory infections (5.8%) were observed. In netilmicin + metronidazole group (44 patients), two cases of wound infections (4.9%), three cases of urinary infections (7%), three cases of respiratory infections (7.5%) and one case of intra-abdominal infection were observed. Our data confirmed that in colorectal surgery, the association pefloxacin, drug with microbiological and pharmacokinetics characteristics suitable for prophylaxis + metronidazole, active against anaerobes pathogens, prevents post-surgical infections as well as a reference association (netilmicin + metronidazole), with the advantage of a single administration.     

A graphical tool for parasite genome annotation

A graphical tool to facilitate rapid primary annotation of genomic sequence has been developed. Within a single interface the user can import sequences or database entries, run feature prediction programs and similarity searches, filter results, add additional manually found features and notes, and finally export annotations for database submission. Integrated rule-based feature corroboration and a novel decision support heuristic using ORF orientation, length and base-composition further enhances the efficiency of the annotation process without compromising flexibility. The program has been explicitly tailored to use in protozoan parasite genome projects, but can constitute a useful tool for prokaryote annotation as well. It is successfully being used by our lab in the Trypanosoma cruzi genome project, and can be obtained from the authors upon request.     

Improved emission uniformity from a liquid-jet laser-plasma extreme-ultraviolet source

Many modern compact soft-x-ray and extreme-ultraviolet (EUV) imaging systems operate with small fields of view and therefore benefit from the use of small high-brightness sources. Such systems include water-window microscopes and EUV lithography tools. We show that the photon losses in such systems can be minimized while uniformity of object-plane illumination is maintained by controlled scanning of the source. The improved collection efficiency is demonstrated both theoretically and experimentally for a scanned laser-plasma source compared with static sources. A prospective aerial image microscope and a liquid-xenon-jet laser-plasma source are offered as examples of modern imaging tools that may benefit from such scanning of the source.     

Intermittent melphalan and prednisolone therapy in plasma cell myeloma

Thirty-two consecutive, previously untreated patients with plasma cell myeloma were treated with 4-day courses of melphalan (0.25 mg/kg/day) and prednisolone (2 mg/kg/day) every sixth week. The observation period ranged from 26 to 75 months and the total median survival time was 29 months. 75% of the patients responded to therapy and their median survival time was 42 months. Sex did not influence either the response rate or the survival time. Most patients were treated in an out-patient clinic and required a minimum of check-ups.     

Dynamic intuition in military command and control: why it is important,and how it should be developed

This paper considers combat dynamic intuition (CDI). We define CDI as the cognitive capability possessed by a military commander when conducting operations. The paper serves two purposes: firstly, we briefly review the previous research on decision making and learning in dynamic systems, in order to discuss the role of microworlds as training environments to improve CDI. In particular, we focus on the advantages of applying system dynamics techniques when designing microworlds to represent "real world" operational challenges. Secondly, we draw implications from a microworld-based experiment, where task complexity is the manipulated variable. The results indicate that environment simplification in itself is not enough to enhance learning in a microworld setting—a conscious pedagogical program, aimed at increasing the training intensity, should also be developed in support of such training. The latter suggestion should be considered an opportunity for further research on CDI improvement.

Molecular tweezers and clips as synthetic receptors. Molecular recognition and dynamics in receptor-substrate complexes

The molecular tweezers (1, 2) and clips (3-7) containing naphthalene and benzene spacer units can be synthesized via repetitive Diels-Alder reactions by the use of a molecular "Lego" set consisting of bisdienophiles (8, 9, 14) and dienes (10, 13). The new receptors selectively bind electron-deficient neutral and cationic substrates in solution. Only the benzene-spaced tweezers form complexes with aliphatic substrates, whereas the other receptors bind aromatic substrates preferentially. HPLC studies with 1 and 2 chemically bonded to stationary phases give similar results for the heterogeneous systems. The formation of stable complexes between the water-soluble clip 5g and N-alkylpyridinium cations, such as N-methylnicotinamide and NAD(+), in aqueous solution illustrates the importance of the hydrophobic effect for arene-arene interactions. The dynamics of the complex formation and substrate mobility were investigated by the use of temperature-dependent liquid- and solid-state NMR spectroscopy. The electrostatic potential surface (EPS) of 1-7 is calculated to be surprisingly negative on the concave side of each molecule and, hence, complementary to the EPS of the electron-deficient substrates, suggesting that the attractive receptor-substrate interaction is here of predominantly electrostatic nature.